Art of transmitting intelligence.



No. 7ll,445. Patented Oct. l4; I902.

v 1 H. SHOEMAKER.

ART OF TRANSMITTING INTELLIGENCE.

filed Sept. 23, 1902.)

(Application 2 Sheets-Sheet I.

(No Model.)

No. 7||,445. Patented. 001. I4. I902.

H. SHOEMAKEB,

ART OF TRANSMITTING INTELLIGENCE.

(Application filed Sept. 23. 1902.) (No Model.) 2 Sheets-Sheet 2.

25%265563. fivenior.

Mai 6341f THE uonms PEYERS co. Pnmam'mu, wuumamm n. c.

. UNITED STATES PATENT OFFICE- HARRY SHOEMAKER, OF PHILADELPHIA,PENNSYLVANIA, ASSIGNOR TO THE CONSOLIDATED WIRELESS TELEGRAPH ANDTELEPHONE COMPANY AND MARIE V. GEHRING, OF PHILADELPHIA, PENNSYLVANIA.

ART OF TRANSMITTING INTELLIGENCE.

SPECIFICATION forming part of Letters Patent No. 711,445, dated October14, 1902.

Original application filed September 16, 1902, Serial No. 123,653.Divided and this application filed September 23. 1902. Serial (Nomodel.) I

To all whom it may concern.-

Be it known that I, HARRY SHOEMAKER, a citizen of the United States,residing at Philadelphia, county of Philadelphia, and State ofPennsylvania, have invented a new and usei'ul Improvement in the Art ofTransmitting Intelligence, of which the following isa specification.

My invention relates toa method of transro mitting intelligence by meansof electroradiant energy transmitted through the natural media.

My invention is a method of transmitting signals, more particularly themethod of receiving the electroradiant energy and causing it to producesignals by causing the energy received to produce manifestation by meansof an electrodynamometer, which is, in fact, the wave-responsive deviceof my system.

My invention consists also in a method whereby feeble energy received ismost efficiently used in producing a signal.

My invention consists also of a method of employinganelectrodynamometerin a closed, resonant, or tuned circuit, theelectrodynamometer winding or windings forming a part of or the entireinductance of such circuit.

My invention consists, further, in a method of producing a signal whichconsists in conmeeting a winding of an electrodynamometer in a circuittraversed by oscillatory currents derived from the receivedelectroradiant energy while subjectingthe other winding to oscillatorycurrents derived from a local source ofenergy, such local. currentsbeing of a frequency less than, equal to, or greater than the frequencyof the transmitted energy.

My invention consists also in a method of maintaining a magnetic fieldby means of a local source of oscillatory currrents and subjecting tothe action of such magnetic field means for producing another magneticfield due to the oscillatory currents derived from the receivedelectroradiant energy.

My invention consists, further, in producing a magnetic field by thereceived electroradiant energy and maintaining a second magnetic fieldby means of the increased current component of energy in a closed,tuned, or resonant circuit.

Myinvention consists, further, in including one of the windings of anelectrodynamometer in a closed, tuned,or resonant circuit traversed bycurrents due to the received electroradiant energy while including theremaining winding of the electrodynamometer in a circuit supplied byoscillatory currents from a local source of energy.

My invention consists, further, in subjecting one of the windings of anelectrodyna- 6o reversal of currents in one winding is simultaneous withthe reversal of current in the remaining winding, and therefore thereaction of the magnetic fields due to these windings is always in thesame direction. I employ the force exerted by the windings of aneleotrodynamometer upon each other due to the currents produced byelectroradiant energy to control a local circuit including the signalrecording or producing apparatus. I have found that with the currentsproduced at a receiving-station by electroradiant energy I can by meansof an electrodynamometer suitably constructed and arranged produce forcesufficient to control local circuits for the purpose of operating signalrecording 0 or producing means.

Reference is to be had to the accompanying drawings, in which Figure 1is an elevational View, partly in diagram, of an electrodynamometerinstru- 5 inent. Fig. 2 is a partial plan view from the top of theelectrodynamometer shown in Fig. 1 with the support shown in section.Fig. 3 is a partial plan View looking upwardly toward the member 18.Fig. 4 is a diagrammatic view showing the electrodynamometercoilsconnected in series with each other and in series with the usual aerialconductor of a wireless signaling system. Fig. 5 is a diagrammatic viewof a closed, resonant, or tuned circuitincludedin the aerial conductor,the windings of the electrodynamometer forming a portion of theinductance of the said closed, resonant, or tuned circuit. Fig. 6 is adiagrammatic view of a modified arrangement of the receiver-circuits.Fig. 6 is a fragmentary view showing the circuit-controlling contacts induplicate in connection with the movable coil of the electrodynamometerwhen employed as shown in Fig. 6 and others. Fig. 7 is a diagrammaticview of transmitting-0ircuits. Fig. 8 is a diagrammatic view showing oneof the windings of an electrodynamometer in a closed, resonant, or tunedcircuit traversed by currents derived from a local source. Fig. 9 is adiagrammatic view similar to Fig. 5, except that one of the windings ofthe electrodynamometer is supplied by oscillatory currents from a localsource. Fig. 10 is a diagrammatic view similar to Fig. 5, except thatone of the coils of the electrodynamometer is included in I a closed,resonant, or tuned circuit and traversed by currents derived from alocal source.

In Fig. 1, 1 represents a base from which rise two supports 2,supporting at their upper extremities member 3. Members 1 2 3 arepreferably of insulating material. 4 represents the stationary coil ofthe electrodynamometer, within which is supported the movable coil 5,which carries relatively heavy supporting means, as clearly shown, andto these means are secured the torsional metallic ribbons 6 and 7. Theupper ribbon 6 is joined at its upper end to the torsion-head 1.0, whilethe lower ribbon 7 is connected at its lower extremity to the leaf 8,which is in electrical communication with the binding-post 9. 11 and 12are binding-posts for stationary coil 4. 13 is the movable contactin thelocal circuit to be controlled and is of a form clearly shown in Fig. 3and constitutes a U-shaped metallic spring secured at its inner end tothe extension from coil 5 and contacting with its outer end with thescrew 14, which passes through 2 and is screw-threaded in the lug 39,extended from the lower side of the member 18. Stationary coil 4 is, infact, two coils slightlyseparated from each other by insulatingmaterial, as shown in Figs. 2 and 3, and through said insulatingmaterial are openings at opposite ends of the diameter, through whichpass the extension from coil 5.

In Fig. 2 the upper opening is shown at 21.

In Fig. 3, 19 represents a corresponding opening in member 18 to permitthe passage of said extension from coil 5.

In Fig. 3, 20 represents a coun terpoise which is, in fact, a nutengaging a screw-threaded extension of the contact 13. By means of thiscounterpoise the center of gravity of the moving system may be kept inthe vertical geometric axis. 15 is a binding-postin electricalcommunication with the screw 14, and from said binding-post 15 extends aconductor from the relay 16 or other recording device in alocal circuit,including battery 17, binding-post 9, ribbon 7, and contact 13. Arepresents the usual aerial conductor of a wireless signaling system andconnects at its lower extremity with binding-post 12, which thencommunicates with one terminal of coil 4, whose remaining terminalconnects by binding-post 11 and conductor with ribbon 6, the coil 5,ribbon 7, spring 8, and earth-plate E. This is precisely the arrangementof connection of the electrodynamometer. Upon the reception ofelectroradiant energy upon an aerial conductor alternating currents ofvery high frequency pass through the coils of the electrodynamometer,and by the well known reaction the moving coil 5 is slightly displacedand in virtue of such displacement closes the local circuit at contacts1.3 and 14. The circuit shown in Fig. 4 is the simplest mode ofconnection for an electrodynamometer, and in this connection it is to beremembered that the inductance of the windings of the electrodynamometermay operate as a frequency-determining element for rendering thereceivingcircuit selective of or resonant with the transmitted energy.

In Fig. 5, A represents the usual aerial conductor, between which andthe earth-plate E is connected the closed,tuned, or resonant circuitembracing the condenser 22, inductance 23, and the coils 4 and 5 of anelectrodynamometer. As is well understood, by the reception ofelectroradiations of a definite frequency and with the condenser 22 andthe combined inductance of the coils 4 and 5 and inductance 23, havingcertain critical proportions, there will fiow in the local circuit,including the condenser 22, the windings of an electrodynamometer, andthe inductance 23, a relatively large current. In other words, of theenergy received at thereceiving-station the current component of theresulting electric-current energy is increased by this arrangement ofcircuits, though of course the actual energy is in no way increased.However, since the magnetic fields depend for their strength simply uponthe ampere-turns of their respective coils a gain is made by increasingthe current component for the purpose of increasing said ampere-turns.With this increased current through the windings of theelectrodynamometer-coils 4 and 5 there is then an increased reactionbetween such coils for the same amount of energy arriving, and theeffect is greater than with the arrangement shown in Fig. 4. Coil 5, asexplained heretofore, is the moving coil and controls the local circuit.

In Fig. 6,A represents the usual aerial conductor, between which and theearth-plate E is connected a coil of an electrodynamometer, and in thiscase it is the moving coil 5. The stationary coil 4 is not in electricalcomm unication with the aerial conductor, nor is it traversed by anysuch current resulting from the received electroradiant energy. It is,however, traversed by oscillatory currents derived from a local sourceof energy 26, which is a battery in series with interrupter 27 and theprimary of transformer 25, whose secondary is shunted to the spark-gap28.

The spark-gap 28 is in series with the condenser 24, stationary'coil 4,and the adjustable inductance 29. This circuit, including condenser 24,stationary coil 4, and adjustable inductance 29, is traversed by analternating current of afrequency dependent upon the capacity 24 and thecombined inductance of the coil 4 and inductance 29. The condenser 24 isadjustable also, and by adjusting either the condenser 24 or inductance29, or

both, the frequency of'the alternating curt0,for then a considerablecurrent can be made to traverse the coil 4, and such coil 4 will inconsequence develop a relatively powerful magnetic field. The result is,then, that the product ofthe ampere-turns of the two coils is increased,and therefore with a relatively small amount of received energy arelatively powerful deflection of the movable coil may be obtained. Theprinciple is the same as that employed in dArsonval galvanometers ofThomsons siphon-recorders, where a light movable coil is traversed by avery weak current, and such coil is supported in a very powerfulmagnetic field in order that the resulting deflection may be a strongone. this arrangement coil 5 may be of comparatively large number ofturns of relativelysmall conductor, while coil 4 may be of comparativelylarge conductor and few turns. Inasmuch as coils 4 5 in this arrangementare independent, the coil 5 may rotate either in a clockwise directionor a counter-clockwise direction, depending upon the relative phaserelation of the arriving energy and the energy in the coil. To insureclosure of the local circuit in whichever direction the coil 5 maystart, I supply, as shown in Fig. 6*, two contacts 37 and 38. nected"together, and the contact 36 corresponds with the contact 13 in Fig. 1.tacts 37 and 38 correspond with contact 14 in Fig. 1. Theaerialconductor A and the very few oscillations.

Contacts 37 and 38 are con- Con-.

coil 5 may be made selective of or resonant with the transmitted energy.Similarly by adjusting the condenser 24 or the inductance 29, or both,oscillations through the coil 4 may be made equal in rate to that of thetransmitted energy. However, if the period of the current through thecoil 4 is either greater than or less than the period of the receivedoscillations the instrument will still be operative. The circuit 24 2829 4 may be said to be adjusted to resonance with received energy, inwhich case the period of the current through coil 4 is equal to theperiod of the received energy.

In Fig. 7, A represents the usual aerial conductor of atransmitting-station, in series with which and the earth-plate E is thespark-gap 34. In shunt to the spark-gap 34 is a condenser 35 ofrelatively great capacity, whose connections to the spark-gap 34 arethrough conductors which are short and thick, and therefore ofnegligible inductance. In shunt to the spark-gap '34 is the secondary ofthe transformer 32, in whose primary is the interrupter 30, source ofenergy 31, and key 33. This transmitter will radiate very forcibly andwill emit a large amount of energy in a This will cause at the receiverthe reception of a large amount of energy in an extremely short time,which is beneficial in a system as herein described.

It is to be understood that the movable coil.

of the electrodynamometer is to be extremely light, delicately supportedor pivoted, and having a very small inertia, so it will respond quicklyand accurately to the received entoo ergy. It is preferable to constructthe moving coil of a conductor of aluminium, as is common practice inelectrodynamometer instruments employed in making measurements inelectric lighting, &c. In an electrodynamometer which I have employed'for recording signals transmitted by electrorad iance energy I haveconstructed the fixed coil of sixteen turns of No. 18 Brown & Sharpegage-wire,while the movable coil is constructed of eight turns of thesame-sized wire. The diameter of the fixed coil was approximately oneand one-fourth inches in diameter and the movable coil made as large aspossible,and yet capable of free movement within the fixed coil. Themovable coil was mounted upon jewel pivot-bearings and was opposed inits motion by a very weak flat spiral spring, one end of which wasconnected to a pivot-pin, while the otherend was secured to the frame ofthe apparatus. g

In Fig. 8, A represents the aerial conductor, between which and theearth-plate E is connected a coil 5 of theelectrodynamometer. In thisinstance it is the movable coil, though of course the stationary coilmight be so connected. The aerialcircuit, including coil 5, may, ifdesired, be selective of or resonant with the transmitted-waves. Theremaining coil 4 is in an independent circuit supplied byalternating-currents from the secondary winding 47 of a transformerwhose primary is shown at 46. 39 is a source of energy, 40 aninterrupter, and 41 a switch controlling the primary circuit of thetransformer 42. In shunt to the secondary of the transformer 42 is thespark-gap 43, which is in series relation in circuit with adjustablecondenser 44, adjustable inductance 45, and the primary 46. By adjustingcondenser 44 or inductance 45, or both, the period of the high-frequencyoscillatory currents in the circuit of the primary 46 may be determined.The secondary 47 operates simply as a source of alternating currents ofa frequency equal to or approximately equal to the frequency of thetransmitted energy (greater than or less than such frequencies,depending upon the adjustment of condenser 44 and inductance 45.) Thecoil 4 operates as the inductance element of a closed, resonant, ortuned circuit, of which 48 forms the condenser. By this means thecurrent component of the energy supplied by the secondary 47 isincreased for the purpose described in connection with Fig. 5. In series with coil 4 is the adjustable inductance 4'. It is to be understoodalso that condenser 48 is adjustable, so that by adjusting saidcondenser 48 or inductance 4', or both of them, the constants of thecircuit 44 48 may beproperly determined for the purposes abovedescribed.

In Fig. 9, A represents the usual aerial conductor, between which andthe earth-plate E is connected the local closed resonance or tunedcircuit comprising condenser 49, adjustable inductance 50, and a coil 5of the electrodynamometer. Condenser 49 is adjustable, so that byadjusting said condenser, inductance 50, or both, the relations of theconstants of the local circuit may be so proportioned as to cause suchcircuit to be a closed, resonant, or tuned circuit with respect to thefrequency of the transmitted energy. 4 represents the remaining windingof an electrodynamometer and is located in series with the circuitcomprising adjustable condenser 63, spark-gap 52, and adjustableinductance 53. In shunt to the spark-gap 52 is the secondary 51 of atransformer, such as 42 in Fig. 8. The constants of the circuitincluding condenser 63, spark-gap 52, inductance 53, and coil 4 areadjusted so that the high-frequency alternating currents traversing suchcircuit shall be of a period equal to that or approximately equal to theperiod of the received electroradiations. By this arrangement a doubleefiect is obtained. In the first place the ampere-turns in coil 5, dueto the received electroradiant energy, are made as great as possible,and, secondly, the ampereturns of the stationary coil are made verygreat bylresorting to a local source of energy. This then greatlyincreases the product of the ampere-turns of the two coils, resulting ina very forcible deflection.

In Fig. 10 an arrangement is shown by which a still more forcibledeflection may be obtained. Between the aerial conductor A and theearth-plate E is the closed, tuned, or resonant circuit, includingadjustable condenser 54, inductance 55, and one coil 5 of anelectrodynamometer. As previously described, this arrangement produces arelatively great magnetic field by the winding 5 with a certain amountof received energy. The ampere-turns of the remaining coil 4 areincreased by making it either the entire ora portion of the inductanceof a second closed, tuned, or resonant circuit, comprising the coil 4,adjustable inductance 64, and the adjustable condenser 56, which circuitis supplied with energy derived from the secondary of a transformer 57.The primary 58 of this trans former is in series with the spark-gap 59,adjustable inductance 61, and adjustable condenser 60. In shunt to thespark-gap 59 is the secondary 62 of a transformer, such as transformer42. (Shown in Fig. 8.) The pcriod of the alternating currents in thecircuit of the primary 58 is determined by inductance 60 and condenser61. By the arrangement shown in Fig. 10, then, we have a maxi mum numberof ampere-turns in one coil of the electrodynamometer and a maximumnumber of ampere-turns in the remaining coil, due to the increasedcurrent component of alternating currents derived from a local source ofenergy.

It is to be understood that in connection with the invention hereindescribed it is within the ability of one skilled in the art tointerchange the movable and fixed coils of an electrodynamometer in anyof the circuits shown or their equivalents, and, furthermore, to use apivoted coil in place of the coil supported by torsion ribbons or wires.

It is to be understood also that a transmitter other than the one shownin Fig. 7 may be used for example, a transmitter which emits trains ofwaves consisting of a great number of waves, and therefore persistent.

It is to be understood that this system may be employed in connectionwith circuits for a plurality of messages or simultaneously orindependently received.

It is to be understood also that a Thomson balance may be used insteadof an electrodynamometer, as herein shown, in which case one coil or setof coils will displace the movable coil of my electrodynamometer and theother coil or set of coils will displace the fixed coil of myelectrodynamometer.

It is to be understood also that the current component of the energy ofelectric currents may be increased by a step-down transformer as well asby the closed, tuned, or resonant circuit herein described.

This application is a division of my application filed September 16,1902, and bearing Serial No. 123,653.

What I claim is- 1. The method of rendering intelligible transmittedelectroradiant energy representing a signal or message, which consistsin transmitted electroradiant energy represen t ing a signal or message,which consists in producing magnetic fields at an angle of approximatelyninety degrees with respect to each other by the received energy, andproducing a signal by the action of said magnetic fields upon eachother.

3. The method of rendering intelligible transmitted electroradiantenergy representing a signal or message, which consists in transformingthe electroradiant energy into the energy of electric currents,producing magnetic fields by said electric current, and producing asignal by the reaction of said fields upon each other.

4. The method of rendering intelligible transmitted electroradiantenergy, which consists in transforming the received energy into theenergy of electric currents, generating magnetic fields at an angle ofapproximately ninety degrees with respect to each other by saidcurrents, and producing a signal by the reaction of said magnetic fieldsupon each other.

5. The method of rendering intelligible transmitted electroradiantenergy,which consists in transforming the received electroradiant energyinto the energy of electriccurrents, energizing an electrodynamoineterby said currents, and producing a signal by the deflection of a memberof said electrodynamometer.

6. The method of rendering intelligible transmittedelectroradiantenergy, which consists in producing a magnetic field bythe received electroradiant energy, maintaining a second magnetic fieldby locally-produced currents of a frequency approximately equal to thefrequency of the transmitted energy, and producing a signal by theaction of said magnetic fields upon each other.

7. The method of rendering intelligible transmitted electroradiantenergy,which consists in producing a magnetic field due to the receivedelectroradiant energy, maintaining a second magnetic field bylocally-generated energy, and producing a signal by the action of saidmagnetic fields upon each other.

8. The method of rendering intelligible transmitted electroradiantenergy,which consists in producing a field of force by the receivedelectroradiant energy, maintaining a second field of force bylocally-produced currents of a frequency approximately equal to thefrequency of thetransmitted energy, and producing a signal by the actionof said fields of force upon each other.

9. The method of rendering intelligible transmitted electroradiantenergy, which consists in producing a field of force by the receivedelectroradiant energy, maintaining a second field of force bylocally-generated en-- ergy, and producing a signal by the action ofsaid fields of force upon each other.

10. The method of rendering intelligible transmitted electroradiantenergy,which consists in producing a field of force due to the receivedelectroradiant energy, maintaining a second field of forcebylocally-generated energy of high frequency, and producing a signal bythe action of said fields of force upon each other.

11. The method of rendering intelligible transmit-ted electroradiantenergy,which consists in transforming the received energy into theenergy of electric currents, increasing the current component of theenergy of electric currents, producing magnetic field's by the increasedcurrent component, and. producing a signal by the interaction of saidmagnetic fields.

12. The method of rendering intelligible transmitted electroradiantenergy,which consists in transforming the received radiant energy intothe energy of electric currents, energizing an electrodynamometer by theincreased current component of the energy of electric currents, andproducing a signal by the deflection of a member of the electrodynamometer.

13. The method of rendering intelligible transmitted electroradiantenergy,which con- 14:. Themethod of rendering intelligible transmittedelectroradiant energy,which consists in transforming the receivedradiant energy into the'energy of electric currents, in-

creasing the current component of the energy of electric currents,producing a field of force by the increased current component,maintaining a field of force by energy locally generated and having highfrequency, and producing a signal by the reaction of said fields offorce upon each other.

15. The method of rendering intelligible transmitted electroradiantenergy, which consists in transforming the received radiant energy intothe energy of electric currents, producing a field of force by theincreased current component, maintaining a fieldof force by theincreased current component of energy locally generated, and producing asignal by the reaction of said fields of force upon each other.

HARRY SHOEMAKER.

Witnesses:

ALICE T. BURROUGH, MAE HOFMANN.

